1. Field
The present disclosure generally relates to vacuum bag processing of composite laminate, and deals more particularly with a method, apparatus and device for preventing wrinkling of vacuum bags during compaction of the laminate.
2. Background
Vacuum bags are commonly employed to compact uncured composite laminate layups in order to eliminate air, volatiles and excess resin from the layup. As the bag is evacuated, atmospheric pressure is applied to the layup, causing compaction and shrinkage of the layup. During this compaction process, the bag may deform in some areas, causing wrinkles to form in the bag. The applied compaction force may press the bag wrinkles against the surface of the layup, resulting in indentations referred to as “mark-off”.
Mark-off may be undesired in several composite laminate applications, either for aesthetic reasons or because mark-off reduces the performance of the laminate. For example, the presence of mark-off in composite laminate stiffeners may have an undesirable effect on the structural qualities of the stiffener.
Accordingly, there is a need for a method and apparatus for reducing or eliminating wrinkling of vacuum bags during the compaction of composite laminates. There is also a need for a method and apparatus of the type mentioned above which reduces or eliminates mark-off on the surface of a laminate that is compacted using vacuum bag processing.